Mayor Bloomberg’s popularity rating has dropped to its lowest level in five years, in part because of his ardent defense of a proposed mosque several blocks from Ground Zero, according to a poll released yesterday.

New Yorkers’ approval of their third-term mayor (pictured) dipped to 49 percent, down from 56 percent in April, as 53 percent of those surveyed said they disagree with his position on the mosque, according to the Marist survey.

“The mosque is not doing him any good . . . He’s certainly on the wrong side of public opinion on that in the city,” said pollster Lee Miringoff, director of Marist College’s Institute for Public Opinion.

Miringoff said the mosque was not the only driving force behind the 7-point dip in the mayor’s approval rating, noting the heaviest opposition to it comes from Republicans, who are largely still in Bloomberg’s camp.

Of the Republicans polled, 74 percent were against building the mosque and an accompanying cultural center near Ground Zero, while half of the Democrats surveyed expressed opposition.

Bloomberg had a 47-percent approval rating among the Democrats polled, compared to a 55-percent thumbs up from GOP voters. Miringoff attributed the drop in large part to the dismal economy.

“Governing in this kind of economic climate, mayors around the country, governors, presidents, chief executives are getting hurt,” Miringoff said.